I've got a SuperStor Ultra (SS tank, lifetime warranty) and there's a slow leak at the exit point. It happened once before and the installer replaced the tank, but since it was over their one-year warranty, I had to pay for their labor but got a new tank (it came to around $300, if I remember). I'm not sure it was the tank, but it was leak free this time for about 4-years. It's now leaking at exactly the same point. Last time it leaked, I was leaving that afternoon for a vacation, and didn't want to deal with it, so I had them fix it. This time, I'll probably deal with it myself.

It looks like it's leaking from the tank outlet to the reducing T that goes to the T&P valve and the tempering valve on the tank side of the T.

Has anyone had similar problems with a SuperStor? Or, is is just more likely that they didn't tighten the T enough or use a quality pipe dope? The thing needs to be in a specific orientation, and maybe it just needed another turn, or they turned it back to align with the other piping. No evidence of tape. If it isn't the tank, why would it be leak free for several years before leaking? What happens if I take it apart and it is the tank? Will the manufacturer honor the warranty since I'm not a 'pro'? Don't really want to pay another $300+ in labor to have them back, but it would be the simplest solution.

Appreciate any thoughts before I start to tear things apart. It's in the basement, so the slow leak isn't catastrophic, but it needs to be fixed.

Well, I took the T off of the outlet, checked it out carefully and did not see any defects (didn't expect any after 4-years, but who knows), put it all back together and the leak was the same or maybe worse since I'd knocked off all of the accumulated mineral deposits. So, I called the plumbers. One guy came, looked at it carefully and said he was pretty sure it was the tank, he called his office, and later that morning, they came and replaced the tank. The design has changed a little bit meaning it might have been because they had problems (or maybe, this way is just cheaper to manufacture). Anyway, it necessitated some slight plumbing modifications, but since they didn't have to add valves and rearrange pipes like they did on the last replacement, this time, it 'only' cost me a bit over $200, mostly labor. So, the lifetime warranty, since installation, has cost me over $500 in replacement costs...I'm not thrilled, but hope this time, this one lasts a very long time. Hope your results are better.

Humm, not nice. Hopefully, the redesigned ports will prevent this from happening again. While I could have replaced it, technically, living in my condo, I'm not supposed to, thus paying the plumber to do it. Plus, it's easier having them schlep the old tank away and deliver the new one. Here's hoping.

In that video the superstor is connected with pex pipe.
The pex is acting like a dielectric union.
You are sot supposed to use dielectric unions because other electrically isolate the tank and keep any stray electrical charge from dissipating from the tank.
The stray charge can attack the welds and cause it to leak.

Also I have been informed when doing a startup on the phoenix water heater(made by the same company) to make sure there is a pressure reducing valve and expansion tank installed because big fluctuations in water pressure can damage the tank...I wonder if the same thing can happen to the superstor tanks........

Excerpt from the superstor manual:
â€Never use dielectric fittings or galvanized steel fittings on any domestic water connections. Use only copper or brass fittings. Failure to follow this caution will result in premature heater failure. Such failure is NOT covered by warrantyâ€

I was told that if there are regular or even brass dielectric unions installed that a bonding wire needs to be installed across the union to let any electrical buildup dissipate.
And pex would cause a similar situation.

We used brass dielectric unions on our first few installs and had to go back and bond across the union, since then only copper or stainless unions are used.

It might have something to do with the welding process and material...I can't find the source right now but I remember reading that welds on stainless can create a place for corrosion due to the heat and filler material.

I don't have an definitive answer, I do know that all of the ones we have replaced were due to leaks at a weld, and all were installed with dielectric unions, none of the ones we installed without dielectric unions(or bonded across one we did use) have not failed yet.
For whatever its worth...